1. Field of the Invention
The present invention relates to a film forming apparatus and to a method for driving the film forming apparatus and also to a device manufacturing method, a device, manufacturing apparatus, and a device.
2. Description of Related Art
The use of electronic devices and photoelectric devices such as liquid crystal display devices has increased along with the development of electronic instruments typified by computers and portable information terminal instruments. For example, this type of liquid crystal display device employs color filters, in order to colorize a display image. These color filters have a substrate and are formed by supplying red (R), green (G), and blue (B) ink in a predetermined pattern to the substrate. An example of such a method of supplying ink to the substrate is one in which an inkjet system of film forming apparatus is employed.
When an inkjet system is used a predetermined quantity of ink is supplied by being discharged onto the substrate from an inkjet head in a film forming apparatus. Devices that use a piezoelectric element are widely used as the ink discharging device. An example of this type of piezoelectric element is one formed by alternately stacking an electrode and a piezoelectric material in a sandwich configuration. This piezoelectric element has a structure in which a capacity (i.e., a pressure producing chamber) in the inkjet head is filled with ink, and this ink is then discharged by a pressure wave created by a deformation in the piezoelectric element.
In this type of inkjet head, because there are limits on the viscosity of an ink that can be discharged, it is difficult for high viscosity ink to be discharged. Therefore, conventionally, a technology is provided in which a heater is provided in an ink tank connected to the pressure chamber via a supply aperture. Alternatively, a technology is provided in which heaters are embedded in both the inkjet head and the ink tank. By using these technologies to lower the viscosity of high viscosity ink to a level where it can be discharged, industrial chemicals, with which it has conventionally been difficult to form a film, have become able to be used.
However, in the conventional technologies such as those described above, it is not possible to employ the method of lowering the viscosity by applying heat in the case of inks having rapid drying properties that contain low boiling point solvents or resin components, or in the case of inks whose properties are changed by the application of heat, as is described above. The problem has therefore existed that it has not been possible to improve conditions in which discharge is difficult.
The present invention was conceived in view of the above circumstances, and it is an object thereof to provide a film forming apparatus and a method for driving this film forming apparatus that enable a high viscosity liquid to be constantly kept at the low viscosity, and that enable liquid drops to be discharged stably, and also to a device manufacturing method, a device manufacturing apparatus, and a device.